Originally Posted by Rowan

Interesting. The favourite bikes for Machka and me are our Ti Hasa road bikes. Mine is coming up to 15,000km (I think about 9,000 miles) and also with Al wheels on each. Considering they were bought as just frames and built up by me from those, they have been beaut bikes. Originally meant for long-distance Audax rides, and I think several 400km ones are on the list of what they have done. Another 400 was planned for the weekend that was coming up when the workplace accident happened 4-1/2 years ago.

Now you have indicated the bike in question is Ti, it might be worth checking the bits of the QR that have slots machined into them and face on to the drop outs. If they are worn, which is highly likely as alloy or steel facing on to Ti, new ones or whole QR might be a solution.